On Wed, 17 Sep 2025, Ville Syrjälä <ville.syrj...@linux.intel.com> wrote:
> On Wed, Sep 17, 2025 at 03:33:31PM +0300, Jani Nikula wrote:
>> On Thu, 04 Sep 2025, Ville Syrjälä <ville.syrj...@linux.intel.com> wrote:
>> > On Wed, Sep 03, 2025 at 11:32:03PM +0300, Jani Nikula wrote:
>> >> xe does xe_bo_unpin_map_no_vm() on the failure path. Add a common helper
>> >> to enable further refactoring.
>> >>
>> >> Signed-off-by: Jani Nikula <jani.nik...@intel.com>
>> >> ---
>> >> drivers/gpu/drm/i915/display/intel_fbdev_fb.c | 5 +++++
>> >> drivers/gpu/drm/i915/display/intel_fbdev_fb.h | 1 +
>> >> drivers/gpu/drm/xe/display/intel_fbdev_fb.c | 7 ++++++-
>> >> 3 files changed, 12 insertions(+), 1 deletion(-)
>> >>
>> >> diff --git a/drivers/gpu/drm/i915/display/intel_fbdev_fb.c
>> >> b/drivers/gpu/drm/i915/display/intel_fbdev_fb.c
>> >> index 3837973b0d25..6b70823ce5ef 100644
>> >> --- a/drivers/gpu/drm/i915/display/intel_fbdev_fb.c
>> >> +++ b/drivers/gpu/drm/i915/display/intel_fbdev_fb.c
>> >> @@ -51,6 +51,11 @@ struct drm_gem_object *intel_fbdev_fb_bo_create(struct
>> >> drm_device *drm, int size
>> >> return &obj->base;
>> >> }
>> >>
>> >> +void intel_fbdev_fb_bo_destroy(struct drm_gem_object *obj)
>> >> +{
>> >> + /* nop? */
>> >
>> > gem_object_put() is what destroys the bo on i915, so I think you're
>> > introducing a leak in the next patch with this nop implementation.
>> >
>> > xe seems to be riddled with footguns here since it conflates
>> > creation+pinning+whatever in the same thing (and I guess it
>> > doesn't know how to clean all that up when the last reference
>> > to the object disappears?) and you have to use that horribly
>> > misnamed function instead...
>>
>> Hmm, can we just slap i915_gem_object_put(obj) in there?
>
> That would at least match how it behaves currently. Though I
> didn't look too deeply whether that is 100% sufficient to clean
> up properly.
I'm doing just that in [1].
[1]
https://lore.kernel.org/r/22bc3c3158f5a22ab258ada8684766fdf75fefec.1758184771.git.jani.nik...@intel.com
>>
>> The i915 variant of intel_fbdev_fb_alloc() ignores errors from
>> intel_framebuffer_create() and just unconditionally does
>> i915_gem_object_put() afterwards:
>>
>> fb = intel_framebuffer_create(intel_bo_to_drm_bo(obj),
>> drm_get_format_info(display->drm,
>> mode_cmd.pixel_format,
>> mode_cmd.modifier[0]),
>> &mode_cmd);
>> i915_gem_object_put(obj);
>>
>> return to_intel_framebuffer(fb);
>>
>> Presumably the refcounts are handled correctly either way.
>>
>> It's just a bit fishy that the potential error pointer from
>> intel_framebuffer_create() goes through to_intel_framebuffer() to the
>> caller.
>
> Yeah, would be less confusing to just check for the error
> explicitly.
Added a new patch for that [2].
[2]
https://lore.kernel.org/r/17631db227d527d6c67f5d6b67adec1ff8dc6f8d.1758184771.git.jani.nik...@intel.com
Together, I believe [1] and [2] keep the current behaviour
intact. Whether that's 100% correct or not, I couldn't say, but at least
I'm shouldn't be introducing any new issues.
BR,
Jani.
--
Jani Nikula, Intel
